1. Field of the Invention
The present invention relates to patterning devices. In particular, the present invention is directed to a method and system for preparing data to be used by a patterning device.
2. Background Art
A patterning device is used to pattern incoming light. A static patterning device can include reticles, also referred to as masks. A dynamic patterning device can include an array of individually controllable elements that generate a pattern through receipt of analog or digital signals. The algorithm used to control the dynamic patterning device, so that its individually controllable elements are in a proper state to form a desired pattern, is called a rasterization algorithm or optical rasterization algorithm. Example environments for use of the patterning device can be, but are not limited to, a lithographic apparatus, an optical maskless lithography (OML) apparatus, a projector, a projection display apparatus, or the like.
Current optical rasterization algorithms can require significant memory and/or CPU-time from a patterning apparatus. For example, optical rasterization algorithms used in OML require the manipulation of mask vector data at multiple grid positions in the array of individually controllable elements to ensure accurate printing of a mask pattern regardless of where the pattern edges lie with respect to the array grid. If the data manipulation is done off-line, the results need to be stored, which can require significant memory. If, on the other hand, the data manipulation is done in-line, significant CPU time is required.
Therefore, what is needed is an improved optical rasterization algorithm that reduces the amount of memory and/or CPU-time required from the patterning apparatus. In addition, the improved optical rasterization algorithm should be able to correct for a variety of distortion errors.